The present invention relates to an air conditioning system for a vehicle, and more particularly to an air conditioning system for a vehicle having at least three rows of seats in the longitudinal direction of the vehicle.
Heretofore there has been an RV (recreational vehicle) having three rows of seats (front, middle and rear seats) in the longitudinal direction of the vehicle in which a cooling outlet and a heating outlet are provided for each of the front, middle and rear seats to ensure satisfactory air conditioning for all of occupants on those seats.
In such an RV, however, seat slide ranges (position adjusting ranges) in the vehicular longitudinal direction of the middle and rear seats are wide, so for example when the middle seat is moved largely to the rear seat side, the distance between the air outlet for the middle seat and the sitting position of the middle seat occupant increases remarkably, so that it becomes difficult for the blown out air to reach the middle seat occupant.
In JP-A No. H10-86628 there is disclosed an air conditioning system wherein the position of a front seat in the longitudinal direction of a vehicle is detected and the volume of air blown out to the front seat occupant is adjusted in accordance with the distance between an outlet for the front seat and the front seat.
Where it is difficult for the blown out air to reach any of the three rows of seats in the foregoing vehicle, if the volume of air is adjusted and increased as in the aforesaid publication, it is possible to solve the described problem. However, the air which has been diffused to another occupant as a result of the increase in air volume creates a draft, thus making another occupant uncomfortable. If the air volume is increased merely to solve the deteriorated cooling or heating, an air conditioning having a large capacity is required, causing an increase in the load of a refrigerant compressor during cooling, with consequent increase in the driving force of the refrigerant compressor.
In an air conditioning system in which engine cooling water is used as a heat source for heating air with an increase in efficiency of a vehicle engine, the heat source during heating becomes insufficient as the volume of blown out air increases, thus giving rise to the problem that the temperature of blown out air drops.
The present invention has been accomplished in view of the above-mentioned drawbacks and it is therefore an object of the invention to provide an air conditioning system for a vehicle having at least three rows of seats in the longitudinal direction of the vehicle, which can ensure cooling and warming of vehicle occupants while suppressing an increase in air volume no matter in what vehicular longitudinal positions the occupants may sit.
For achieving the above-mentioned object, in a first aspect of the present invention there is provided a method for controlling an air conditioning system for a vehicle having three or more rows of seats in the longitudinal direction of the vehicle, the seats being adjustable in their vehicular longitudinal positions, the air conditioning system being mounted on the vehicle and having plural air blow out outlets in the vehicular longitudinal direction, which method comprises detecting a sitting position of a vehicular occupant in the vehicular longitudinal direction, selecting an outlet located near the occupant""s sitting position out of the plural outlets based on the detected sitting position, and blowing out air from the selected outlet toward the occupant""s sitting position.
Thus, since the outlet located near the occupant""s sitting position is selected and air is blown out from the selected outlet, it is easier for blown out air to reach the occupant. Specifically, with a small volume of blown out air, the occupant is sufficiently cooled or warmed. Also, since the volume of air blown out toward the occupant can be reduced, there is no fear of draft air flowing toward another occupant of the vehicle.
Moreover, since the blown out air volume for a vehicular occupant can be diminished, in an air conditioning system provided with a refrigerant compressor, it is possible to decrease the load on the refrigerant compressor during cooling, and thereby decreasing the driving force of the refrigerant compressor.
Further, since the blown out air volume for a vehicular occupant can be diminished, in an air conditioning system wherein engine cooling water is utilized as a heat source for heating blast air, it is possible to prevent a lowering in temperature of blown out air during heating and hence sufficiently warming the occupant.
In a second aspect of the present invention there is provided, in combination with the above first aspect, a vehicular air conditioning system controlling method wherein the temperature or volume of the air blown out from the outlets is controlled according to the sitting position of the vehicle occupant.
According to this method, for example during cooling, by reducing the temperature of blown out air with an increase in the distance between the vehicle occupant and the associated outlet, a sufficient cool feeling can be given to the occupant with a reduced volume of blown out air.
In a third aspect of the present invention there is provided, in combination with the above first or second aspect, a vehicular air conditioning system controlling method wherein whether an occupant is sitting on a seat is detected for each of the seats and air is blown out to only the seat on which the occupant sits. According to this method, it is possible to decrease the total volume of air blown out from the air conditioning system and thereby further diminish the load on the refrigerant compressor.
In a fourth aspect of the present invention there is provided an air conditioning system for a vehicle having three or more rows of seats in the longitudinal direction of the vehicle. The seats are adjustable in their vehicular longitudinal positions. The air conditioning system has a plurality of air outlets in the longitudinal direction of the vehicle and has a sitting position detecting means for detecting an occupant""s sitting position in the longitudinal direction of the vehicle. An outlet selecting means is provided for selecting, out of the plural outlets, an outlet located near the occupant""s sitting position based on the result of detection obtained by the sitting position detecting means, blow out direction calculating means which calculate a direction in which air is blown out from the outlet selected by the outlet selecting means. This is based on the detection obtained by the sitting position detecting means, and blow out direction adjusting means which are controlled based on the calculation obtained by the blow out direction calculating means and which adjust the blow out direction of air from the outlet selected by the outlet selecting means.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are intended for purposes of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. In the drawings: